Drug aficionados: What are the customs and appropriate rules of behavior for buying and selling illicit drugs? Is it really ok to bring a switchblade to the deal in order to stab the plastic bag and test the quality of the llello?

Drug dealers don't deal with people they don't know. If a random person wants to buy a large amount of drugs, it's either a robbery or the cops, neither is worth the risk. Drug dealers are incredibly risk-averse, and not stupid. Large amounts of hard drugs will usually be bought or sold in a neutral environment, between people who are familiar with each other, and if you're trying to pass of something other than drugs as the real thing, you are risking your life. What a lot of people don't know is that organized crime is often a mediator for such problems, if there is a dispute between 2 parties and you can't resolve it with the law, then a group like a certain biker gang will often mediate the dispute for a heavy price. Justice isn't free.